Spray coating machine



. SPRAY COATING MACHINE Filed April 2, 1931 a "win X I I N 3 Mm, n

INVENTQR BM mw Patented July 3, 1934 UNITED STATES,

SPRAY COATING MACHINE Wayne B. Roberts, Mount Lebanon, Pa., assignor to Aluminum Company of America, Pittsburgh, Pa., a corporation of Pennsylvania Application April 2, 1931, serial No. 527,087

ZCIaimS.

This invention relates to spray coating machines, and more particularly to that type which includes a casing forming a coating chamber, and means for passing material through ,the

'5 casing in a straight line while it is being spraycoated in the chamber.

Due largely to the relatively fixed position of spray nozzles in the coating chambers of such machines as have been 'used for spray coating.

lumber, especially those used for prime coating, the machines have not been economical in respect to the quantity of paint used. This is particularly true when they are used to prime coat lumber of different sizes, and lumber variously mortised, grooved, and otherwise irregularly cut.

Also, in some machines difliculty has been experienced in so controlling the directions of the sprays as to avoid their interference with one another, and in so mounting the nozzles as to go obtain uniformity of coating.

The object of this invention is to improve the construction of spray coating machines of the type mentioned so that they may be used to economically, and with substantial uniformity, coat various articles, such as lumber of various sizes' and provided with various irregular cuts.

The invention is illustrated inthe accompanying drawing in which Fig. 1 is a side elevation,

partly in section, of a spray coating machine;

Fig. 2 an end elevation thereof, partly in section; Fig. 3 enlarged detail view showing a nozzle and its adjustable mounting; and Fig. 4 an enlarged detail view of a shield for,proa section of a piece of lumber from the spray.

In the practice of my invention, a spraycoating'machine, comprising a casing and means for passing material through it in a straight line,

is provided with means for supporting a plurality of spray nozzles in variable angular positions around the line of passage of articles through the casing. Preferably, such nozzle supports are arranged at both the entering and discharge end of the casing so that sprays of paint or other coating material may be directed upon all exposed surfaces of articles passing through the casing. While various forms of nozzle supports mmag be used, each is preferably a continuous In the illustrative embodiment of the invention a casing forming a coating chamber 1 is provided with a flue 2, to which a fan or other exhausting means may be connected, and is supported upon a frame structure 3. The top 'portion of the casing is semi-circular in cross section, and is provided'with a door 4 to permit access to the chamber. The bottom portion of the casing is sloped from all sides toward the center where a drip pipe 5 is located for drawing off excess paint accumulating within the 60 chamber during the spraying operation. Rigidly connected to each end of the casing are conical housings 6, the sloping surfaces of which are adapted to be closed by means of cover plates 7. These may be slidably held in place by means 05 of spring clips 8 attached to the housings so that the plates can be moved around the housings to any desired position, or be removed entirely, the Purpose of which will presently be pointed out.

The lumber to be coated is carried by a belt 10 conveyor 9 into chamber 1, the ends of housings 6 being provided with openings 10 to permit it to be carried through the coating machine. Within chamber 1 there is a series of conveyor, rollers in the form of spiked discs 11, secured to shafts 15 12 which are rotatably mounted in bearings 13 secured to frame 3. At the discharge end of the machine there is a belt conveyor 14 provided with a plurality of outwardly extending spikes 15 tocarry lumber, without smearing it, to a drying go furnace or storage place. Shafts 12 may be driven by means of sprockets 16 and a chain 1'1- from conveyor 14.

Spray gun or nozzle supports, in the form of rings 18, are attached to the ends of the housings 95 by means of braces 21, additional stabilizing braces 22 extending from the ringsto frame 3. A plus rality of spray guns or nozzles 23 are slidably mounted on rings 18, being attached to them by means of clamps 24. To eifect further adjustment of the nozzles, each is preferably 'pivotally attached by a link 25 to one end of a rod 26, the other end of which is slidably and rotatably mounted in a clamp 24, the rod being held in any desired adjusted position by a set screw 2'1; Air and paint are supplied to the guns through fle'xible conduits 28, the supply being so regulated as to give the required amount of coating. .Alth'oughaminiuiumofonegunoneachringis considered essential to spray a board of uniform 0 cross section, by adding more guns to the rings, the capacity of the machine can be increased and irregular articles may be properly coated. Shields 29 (Fig. .4), adjustably mounted within chamber 1, may be so positioned as to permit spraying any specified portion of a piece of lumber, leaving the remainder uncoated. This is particularly advantageous in the coating of window sills and the like, part of which are to be stained later, and which should therefore not have their entire surfaces allows the operator to reach into the chamber and place the shields in the proper positions.

To put the machine in readiness for operation, the spray guns are slipped around rings 18 until the desired positions are reached for the particular size and type of material to be painted, and each gun is then tilted to the proper angle to obtain the most eflicient direction of its spray; The cover plates 7 are slidably attached to housings 6 by means of clips 8 so thatan opening can be left adjacent each gun to permit it or its spray to project into the housing. A trial piece of lumber laid within the chamber will aid in correctly positioning the guns.

When the nozzles are thus adjusted, conveyors 9 and 14 and shafts 12 are set in motion, and lumber from conveyor 9 is fed through opening 10 into the machine where discs 11 pick it up and convey it in a straight line through the machine in the path of the sprays and out of the oppositeber of various width and thickness, and lumber having various grooves, mortises, and other cuts in it, can be properly coated. As the nozzles can always be so directed that their sprays will not interfere with one another, the application of a thicker coat in some places than is necessary can be avoided. The speed of the conveyors and the force and volume of the sprays can be regulated to obtain the desired thickness of coating material. mounted outside the housings, they are always open to inspection, cleaning and repairs. The entire machine is simple of construction, easy to operate, and economical and efficient to use.

The guns being i prime coated or painted. Door 4, when opened,-

According to the provisions of the patent statutes, I have explained the principle and mode of operation of my invention, and have illustrated and described what I now consider to represent its best embodiment. However, I desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically shown and described.

I claim:

1. In a coating machine, the combination with a casing forming a coating chamber, and means for passing material to be coated therein through the chamber in a substantially straight line, of a plurality of nozzles for spraying coating material on articles while passing through the chamber, and means outside of the casing for supporting the nozzles in variable angular positions in relation to the line of passage of articles through the chamber, said casing being provided with a plurality of shutters movable to form openings for the passage of sprays from the nozzles at any of their variable angular positions.

2. In a coating machine, the combination with a casing forming a coating chamber, and means for passing material to be coated therein through the chamber in a substantially straight line, of a plurality of nozzles for spraying coating material on articles while passing through the chamber, a ring at each end and outside of the casing, means for adjustably mounting the nozzles on the rings at variable angular positions with relation to the line of passage of articles through the chamber, a plurality of cover plates slidably mounted on the casing adjacent the nozzles to permit openings through which the nozzles can project into the chamber, and adjustable means for confining the coating to a predetermined area of the article being coated.

WAYNE B. ROBERTS. 

